Not exactly ordering on line. A Works manager in a firm I used to work for back in the 70's, I asked him to order 10 file handles from Radio Spares, which he did. When the order arrived it was 100! What he failed to see that the order quantity was for 1 pack of ten, needless to say he passed the ordering over to me after he found he was the butt end of jokes in the company.
Only a couple of handles were used per year, so the company was safe for the next 50 years.